Rhododendron 'Lady of Spain', which is Lofthouse hybrid documented as 'Mrs. Horace Fogg' x 'Point Defiance', has been determined to be a triploid using flow cytometry by
Dr. João Loureiro, Dr. Silvia Castro, José Cerca, and Mariana Castro
Plant Ecology and Evolution Group,
Centre for Functional Ecology,
Department of Life Sciences,
Faculty of Science and Technology,
University of Coimbra, Portugal.
In the case of triploid 'Lady of Spain', a suspected diploid crossed with a tetraploid produced a triploid indicating that normal reduced meiosis most likely occurred for both parents. In other words, 'Lady of Spain' having 39 chromosomes received 13 chromosomes from the suspected diploid 'Mrs. Horace Fogg' and 26 chromosomes from the tetraploid 'Point Defiance'.
Summary of Ploidy Levels
Triploid 'Lady of Spain',
Tetraploid 'Point Defiance'
Source Marc Colombel
John and Sally Perkins
